An 8 bit programmable 18 GHz frequency divider for mm-wave frequency synthesis

A programmable frequency divider operating up to 18 GHz input frequency is presented. The division ratio can be set between 12 and 255. The complete circuit consists of a divide-by-4/5 prescaler and attached programmable dividers of 2 Bit and 6 Bit. It is designed using differential current-mode logic gates in a high frequency SiGe bipolar technology. The divider operates at a supply voltage of 3.3V and a total power consumption of only 200mW including output drivers and a logic interface for programming the division ratio. The frequency range and the division ratio are appropriate for phase-locked loops in high performance and wide-band measurement systems in the millimeterwave region.